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1.
Zookeys ; 1208: 331-346, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39170810

RESUMO

A new newt species, Hypselotritonhuanggangensis sp. nov., is described based on nine specimens collected from Huanggangshan Mountains, Yanshan County, Jiangxi, China. Morphologically, the new species is characterized by the combination of nine external characters: (1) obvious black patches with clear boundaries on the whole body; (2) ground color of the dorsal body tan; (3) ground color of venter bright orange; (4) skin rough; (5) vertebral ridge weak; (6) fingers and toes overlapping when forelimb and hindlimb adpressed towards each other along body; (7) postocular orange spot absent; (8) small white warty glands around the eye; (9) two discontinuous longitudinal lines formed by white warty glands from neck to lateral parts of tail. Molecularly, the new species forms an independent clade with strong support in the phylogenetic trees of the genus based on the mitochondrial locus of NADH dehydrogenase subunit 2 (ND2) gene fragments. The new species distinctly differs from H.fudingensis by differences in its body measurements, vertebral ridge, dorsal black patches, and ventral black patches. Furthermore, the new species and H.fudingensis are geographically isolated by a series of high mountain ranges, including the Wuyishan and Jiufengshan Mountains. The number of Hypselotriton species is now 11.

2.
J Hazard Mater ; 476: 135110, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970976

RESUMO

Potentially toxic elements (PTEs) in seawater and sediments may be amplified along the aquatic food chain, posing a health threat to humans. This study comprehensively analyzed the concentrations, distribution, potential sources, and health risk of 7 PTEs in multimedia (seawater, sediment and organism) in typical subtropical bays in southern China. The results indicated that Zn was the most abundant element in seawater, and the average concentration of Cd in sediment was 3.93 times higher than the background value. Except for As, the seasonal differences in surface seawater were not significant. The content of Zn in fishes, crustacea, and shellfish was the highest, while the contents of Hg and Cd were relatively low. Bioaccumulation factor indicated that Zn was a strongly bioaccumulated element in seawater, while Cd was more highly enriched by aquatic organisms in sediment. According to principal component analysis (PCA), and positive matrix factorization (PMF), the main sources of PTEs in Quanzhou Bay were of natural derivation, industrial sewage discharge, and agricultural inputs, each contributing 40.4 %, 24.2 %, and 35.4 %, respectively. This study provides fundamental and significant information for the prevention of PTEs contamination in subtropical bays, the promotion of ecological safety, and the assessment of human health risk from PTEs in seafood.


Assuntos
Baías , Monitoramento Ambiental , Peixes , Sedimentos Geológicos , Água do Mar , Poluentes Químicos da Água , China , Poluentes Químicos da Água/análise , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Animais , Água do Mar/química , Água do Mar/análise , Medição de Risco , Organismos Aquáticos , Crustáceos , Frutos do Mar/análise , Bioacumulação
3.
Proc Biol Sci ; 291(2027): 20240818, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043244

RESUMO

Infrared vision is a highly specialized sensory system that evolved independently in three clades of snakes. Apparently, convergent evolution occurred in the transient receptor potential ankyrin 1 (TRPA1) proteins of infrared-sensing snakes. However, this gene can only explain how infrared signals are received, and not the transduction and processing of those signals. We sequenced the genome of Xenopeltis unicolor, a key outgroup species of pythons, and performed a genome-wide analysis of convergence between two clades of infrared-sensing snakes. Our results revealed pervasive molecular adaptation in pathways associated with neural development and other functions, with parallel selection on loci associated with trigeminal nerve structural organization. In addition, we found evidence of convergent amino acid substitutions in a set of genes, including TRPA1 and TRPM2. The analysis also identified convergent accelerated evolution in non-coding elements near 12 genes involved in facial nerve structural organization and optic nerve development. Thus, convergent evolution occurred across multiple dimensions of infrared vision in vipers and pythons, as well as amino acid substitutions, non-coding elements, genes and functions. These changes enabled independent groups of snakes to develop and use infrared vision.


Assuntos
Genômica , Raios Infravermelhos , Animais , Boidae/genética , Boidae/fisiologia , Serpentes/genética , Evolução Molecular , Visão Ocular , Evolução Biológica , Filogenia
4.
Proc Natl Acad Sci U S A ; 121(20): e2320674121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38684007

RESUMO

Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.


Assuntos
Anfíbios , Biodiversidade , Filogenia , Animais , Anfíbios/classificação , China , Conservação dos Recursos Naturais
5.
AAPS PharmSciTech ; 24(5): 132, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291437

RESUMO

Taste masking is critical to improving the compliance of pediatric oral dosage forms. However, it is challenging for extremely bitter lisdexamfetamine dimesylate (LDX) with a long half-life and given in large dose. The present study aims to develop an immediate-release, taste-masked lisdexamfetamine chewable tablet. Lisdexamfetamine-resin complexes (LRCs) were prepared using the batch method. The molecular mechanism of taste masking was explored by PXRD, PLM, STA, and FT-IR. The results showed that taste masking was attributed to the ionic interaction between drug and the resin. The ion exchange process conformed to first-order kinetics. The rate-limiting step of drug release was the diffusion of ions inside the particles, and the concentration of H+ was the key factor for immediate release. The masking efficiency of the prepared LRCs in saliva exceeded 96%, and the drug could be completely released within 15 min in aqueous HCl (pH 1.2). Furthermore, the SeDeM expert system was used for the first time to comprehensively study the powder properties of LRCs and to quickly visualize their defects (compressibility, lubricity/stability, and lubricity/dosage). The selection of excipients was targeted rather than traditional screening, thus obtaining a robust chewable tablet formulation suitable for direct compression. Finally, the difference between chewable tablets containing LRCs and chewable tablets containing lisdexamfetamine dimesylate was compared by in vitro dissolution test, electronic tongue, and disintegration test. In conclusion, an immediate-released, child-friendly lisdexamfetamine chewable tablets without bitterness was successfully developed by the QbD approach, using the SeDeM system, which may help in further development of chewable tablets.


Assuntos
Dimesilato de Lisdexanfetamina , Paladar , Humanos , Criança , Resinas de Troca Iônica/química , Excipientes , Espectroscopia de Infravermelho com Transformada de Fourier , Solubilidade , Comprimidos , Composição de Medicamentos/métodos , Administração Oral
6.
Mar Pollut Bull ; 191: 114905, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37062132

RESUMO

The concentrations, distribution, and risk of seven potentially toxic elements (PTEs), including As, Cd, Cr, Cu, Hg, Pb, and Zn, in seawater and sediment from the eastern Beibu Gulf of China were studied using national standard methods. Results showed that the concentrations of PTEs in seawater exhibited significant spatial and seasonal variations, resulting in tolerable non-carcinogenic and carcinogenic health risks for both adults and children. The sediment concentrations of PTEs were generally lower than historical values, indicating an acceptable pollution level and ecological risk, except for Hg. Granularity was found to be an important factor in regulating the distribution. Furthermore, principal component analysis (PCA) and positive matrix factorization (PMF) model simulation revealed that the sources of PTEs in sediment were primarily of natural origin, with the exception of Hg, which was predominantly of anthropogenic origin. The parent rock of As was different from that of other PTEs.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Criança , Adulto , Humanos , Metais Pesados/análise , Monitoramento Ambiental/métodos , Água/análise , Poluentes do Solo/análise , Mercúrio/análise , Medição de Risco , China , Solo
7.
Mol Ecol Resour ; 23(5): 1124-1141, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36924341

RESUMO

DNA barcoding has greatly facilitated studies of taxonomy, biodiversity, biological conservation, and ecology. Here, we establish a reliable DNA barcoding library for Chinese snakes, unveiling hidden diversity with implications for taxonomy, and provide a standardized tool for conservation management. Our comprehensive study includes 1638 cytochrome c oxidase subunit I (COI) sequences from Chinese snakes that correspond to 17 families, 65 genera, 228 named species (80.6% of named species) and 36 candidate species. A barcode gap analysis reveals gaps, where all nearest neighbour distances exceed maximum intraspecific distances, in 217 named species and all candidate species. Three species-delimitation methods (ABGD, sGMYC, and sPTP) recover 320 operational taxonomic units (OTUs), of which 192 OTUs correspond to named and candidate species. Twenty-eight other named species share OTUs, such as Azemiops feae and A. kharini, Gloydius halys, G. shedaoensis, and G. intermedius, and Bungarus multicinctus and B. candidus, representing inconsistencies most probably caused by imperfect taxonomy, recent and rapid speciation, weak taxonomic signal, introgressive hybridization, and/or inadequate phylogenetic signal. In contrast, 43 species and candidate species assign to two or more OTUs due to having large intraspecific distances. If most OTUs detected in this study reflect valid species, including the 36 candidate species, then 30% more species would exist than are currently recognized. Several OTU divergences associate with known biogeographic barriers, such as the Taiwan Strait. In addition to facilitating future studies, this reliable and relatively comprehensive reference database will play an important role in the future monitoring, conservation, and management of Chinese snakes.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Humanos , Animais , Filogenia , Código de Barras de DNA Taxonômico/métodos , Serpentes/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética
8.
Biodivers Data J ; 11: e103580, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327331

RESUMO

Background: To date, 10 species of the genus Microhyla have been recorded in China, of which six were distributed in Yunnan Province. Microhylahmongorum Hoang, Nguyen, Phan, Pham, Ninh, Wang, Jiang, Ziegler, and Nguyen, 2022 was also speculated to be distributed in Xishuangbana, Yunnan Province, China. However, there is no evidence of documentation of M.hmongorum. New information: We report the first country record of Microhylahmongorum, based on specimens collected from Yunnan border region. Morphologically, the specimen was consistent with the original descriptions of M.hmongorum. Phylogenetically, the sequences of the specimens from China clustered with the sequence of type specimens of M.hmongorum from Vietnam, with uncorrected pairwise distances of 0.9% at the 16S gene fragment analysed. Therefore, we report M.hmongorum as a new record species in China.

9.
Mar Pollut Bull ; 184: 114185, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36194963

RESUMO

Potentially hazardous metals (PHMs) in the coastal environment have become a great concern due to their easy bioaccumulation, poor biodegradability and high toxicity. Surface sediment samples were collected in a subtropical bay in South China to analyse the spatial variations, contamination level and potential sources of PHMs. The results indicated that the order of average contents of PHMs in Qinzhou Bay sediment was Zn > Pb > Cr > Cu > As > Hg > Cd. The most important potential ecological risk factor was Hg pollution in the Qinzhou Bay sediments. The positive matrix factorization (PMF) model results indicated that Cu, Pb, Zn, Cd and Cr mainly originated from natural sources while Hg and As were related to coal fired industrial inputs and petroleum production activities. The results could provide a basis for marine management to formulate relevant pollution prevention and control measures.


Assuntos
Mercúrio , Metais Pesados , Petróleo , Poluentes Químicos da Água , Metais Pesados/análise , Sedimentos Geológicos/análise , Monitoramento Ambiental , Baías , Poluentes Químicos da Água/análise , Cádmio/análise , Chumbo/análise , Medição de Risco , Mercúrio/análise , Petróleo/análise , Carvão Mineral/análise , China
10.
Chem Commun (Camb) ; 58(62): 8690-8693, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35833251

RESUMO

We report a peptidic dual-targeting drug delivery platform (integrins targeting and self-assembly instructed by matrix metalloproteinases) towards inflamed endothelial cells, which improved the anti-inflammatory ability of the loaded drug (i.e., puerarin) in vitro and thus improved the antiatherogenic effect of the loaded drug (i.e., puerarin) in vivo.


Assuntos
Aterosclerose , Células Endoteliais , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Apolipoproteínas E , Aterosclerose/tratamento farmacológico , Camundongos , Peptídeos/farmacologia , Peptídeos/uso terapêutico
11.
Environ Toxicol Pharmacol ; 92: 103834, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35227884

RESUMO

The distribution and risk assessment of heavy metals (Pb, Cu, Cr, Zn, Cd, As and Hg) in the economic fish of the Southern Fujian Province was acquired. The Cd content was below the detection limit. 53.5% of As and 26.7% of Hg were lightly polluted, but the indices of Pin (Nemero comprehensive pollution index) and MPI (metal pollution index) both indicated no pollution. The indices of EDI (estimated daily intake) and THQ (target hazard quotient) both indicated no non-carcinogenic risk of HMs. The index of Ri (average annual cancer risk) verified no carcinogenic risk for Pb and acceptable risk for As. Furthermore, molecular docking results revealed As may have significant reproductive toxicity to humans. Our findings serve to heighten an awareness of economic fish consumption and provide a reference for marine environmental management and food security in study area.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Cádmio , Carcinógenos , China , Monitoramento Ambiental , Chumbo , Metais Pesados/análise , Metais Pesados/toxicidade , Simulação de Acoplamento Molecular , Medição de Risco , Solo , Poluentes do Solo/análise
12.
Mar Pollut Bull ; 174: 113297, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35090281

RESUMO

Cu, Pb, Zn, Cd, Cr, Hg and As in seawater, sediment and organisms of the Daya Bay, Guangdong province, China were measured to acquire the comprehensive understanding on distribution, sources and risk assessment of heavy metals (HMs) in the marine ecosystem. The concentrations were relatively ideal, and the Pb was the major pollutant in the seawater and sediment. The contents of HMs were highest in spring; the concentrations near the sewage outlet and shore were noticeable. Submarine pipeline sewage, atmospheric deposition and runoff were the main sources of HMs in coastal waters. Studied HMs were preferentially retained by liquid phase; Cd, Cu and Zn were the most accumulated elements in the organisms from the surrounding environment. Cd in shellfish deserved particular attention, but the health risks including non-carcinogenic and carcinogenic risks of all elements were within acceptable limits. The potential health risks of Pb have been confirmed by molecular docking.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Baías , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Simulação de Acoplamento Molecular , Medição de Risco , Água do Mar , Poluentes Químicos da Água/análise
13.
Mar Pollut Bull ; 174: 113237, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34923402

RESUMO

In this paper, the distribution, degree of pollution and sources of Cu, Pb, Zn, Cd, Cr, As, Co, Ni and Hg in the surface sediment of Sanmen Bay were studied. The average concentrations of the identified potentially toxic elements (PTEs) were in the following order: Zn > Ni > Cr > Cu > Pb > Co > As>Cd > Hg. Almost all PTEs had a significant positive correlation with TOC, clay and Al; Cr had no significant correlations. Apart from Hg, the contamination levels of 8 PTEs were at those considered to be low-to-no pollution. Comparatively, the contamination level of Hg was much higher than the background value, which indicated moderate pollution. The source of this pollution may have included industrialization, urbanization and/or transport of industrial waste materials. Both geoaccumulation index (Igeo) and potential ecological risk (RI) values suggested that Hg was the major contributor to the ecological risk posed by the selected PTEs.


Assuntos
Metais Pesados , Poluentes do Solo , Baías , China , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise
14.
Mar Pollut Bull ; 174: 113192, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34863072

RESUMO

Given the great importance of Yundang lagoon (China), a detailed evaluation and source identification of multiple potentially toxic elements (PTEs) is required. Low concentrations of the PTEs were found in the Diversion canal, while high in the Main canal, Inner lagoon, and Outer lagoon. Evaluation results indicated that the pollution of PTEs was widespread, and that the extremely high eco-risks and evident toxicity were owing to the great contributions of Hg and Cd. Positive matrix factorization model demonstrated that the PTEs were from both natural and different types of anthropogenic sources. TOC played a critical role in the PTEs. It was also found that the limited environmental carrying capacity and the poor hydrological condition of the lagoon may still accumulate the pollution in a progressive fashion. These findings provide a detailed information on making effective strategies of new directions for long-term prevention of PTEs pollution in the landscape urban lagoon.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Poluição Ambiental , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise
15.
Artigo em Inglês | MEDLINE | ID: mdl-34886201

RESUMO

Potentially toxic elements (PTEs) have attracted substantial attention because of their widespread sources, long residue time and easy accumulation. PTEs in the surface sediments of inshore waters are strongly affected by human activities because these waters are a zone of interaction between the ocean and land. In the present study, to explore the environmental geochemical behaviour and source of PTEs in the surface sediments of coastal waters, the contents and spatial distributions of copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr), mercury (Hg) and arsenic (As) in different regions of Xiamen Bay were investigated. The data were processed by multivariate statistical methods, and the distribution characteristics of PTEs in the surface sediments of Xiamen Bay were analysed. In addition, the pollution load index (PLI), geo-accumulation index (Igeo) and potential ecological index(RI) were used to evaluate the pollution degree and potential risk in the surface sediments of Xiamen Bay, and the positive matrix factorisation (PMF) model was used to analyse the source. The results show that Zn had the highest mean concentration, followed by Pb, Cr, Cu, As, Cd and Hg, among the seven PTEs. The mean contents of Pb, Zn, Cd, Cu and Hg, and especially Hg and Cd, were higher than the corresponding environmental background values. The average PLI value indicated that the Xiamen Bay sediment was moderately contaminated by PTEs. The Igeo results showed that Xiamen Bay was moderately to strongly polluted by Cd and Hg. The proportions of samples with low, medium and strong risk levels were 11.63%, 74.42%, and 13.95% in surface sediments, respectively. PMF models showed that the input of chemical fertilizer and medication, anthropogenic atmospheric components and terrestrial detritus were the main sources of PTEs in the surface sediment of Xiamen Bay.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Atividades Humanas , Humanos , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
16.
Zootaxa ; 5052(2): 41-64, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34810879

RESUMO

The genus Leptobrachella is one of the most speciose and taxonomically troubling groups of Asian anurans. Herein, we describe a new species of Leptobrachella from Doi Inthanon, Chiang Mai Province, Thailand based on the integration of morphological, acoustic and molecular data. The new species, Leptobrachella murphyi sp. nov., is morphologically distinguished from its congeners on the basis of body size, dorsal skin texture and coloration, ventral coloration and pattern, degree of webbing and fringing on the fingers and toes, iris coloration in life, pattern of markings on flanks and pattern of body macroglands. It also differs from its phylogenetically close congeners by an uncorrected p-distance of >9.6% for a fragment of 16S rRNA. The advertisement call of the new species consists of 4.54.7 kHz (at 15 C) and without a distinct introductory note. Leptobrachella murphyi sp. nov. likely occurs across the Thanon Thong Chai Range and analyses provide evidence of unknown biodiversity and species composition on Doi (mountain) Inthanon. In addition, the congeneric species L. minima was also confirmed in Doi Inthanon. The coexistence pattern of Leptobrachella in Doi Inthanon deserves further study. As Thailands highest mountain and biodiversity reservoir, the need for further biological exploration is urgent given ongoing habitat loss and degradation.


Assuntos
Anuros , Ecossistema , Animais , Anuros/genética , Tamanho Corporal , Filogenia , RNA Ribossômico 16S/genética , Tailândia
17.
Biodivers Data J ; 9: e74097, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720641

RESUMO

BACKGROUND: Thailand is considered a global biodiversity hotspot that is known to harbour a striking diversity of endemic species. However, several research studies have determined that the level of amphibian diversity in the country has been significantly underestimated. The megophryid genus Leptobrachella Smith, 1925 is currently known to include 89 species that are primarily distributed throughout southern China and Southeast Asia; however, only seven species have been found in Thailand. NEW INFORMATION: Based on an integrative approach encompassing genetic and morphological analyses, we have concluded that the population identified from Chiang Rai Province of Thailand is conspecific with Leptobrachellaventripunctata (Fei, Ye, and Li, 1990). Importantly, this is the first confirmation record of this species, based on molecular and morphological evidence in Thailand. The discovery of this species reaffirms that the diversity within the genus has been underestimated with many species yet to be discovered. In addition, the findings of our study further highlight the lack of existing knowledge on amphibian taxonomy and an underestimation of the biodiversity that exists along these national border areas.

18.
Zool Res ; 42(5): 620-625, 2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34410048

RESUMO

We describe a new species of the genus Hebius and provide evidence for the validity of H. septemlineatuscomb. nov. Morphological and molecular analyses of Hebius specimens collected in Yunnan Province, China, revealed three distinct lineages, namely the newly described Hebius weixiensissp. nov., as well as H. octolineatus (Boulenger, 1904), and H. septemlineatuscomb. nov. (Schmidt 1925), which is removed from synonymy with H. octolineatus. Based on mitochondrial genealogy, Hebius weixiensissp. nov. is sister to H. septemlineatuscomb. nov., while H. octolineatus is sister to H. bitaeniatus. The new species and H. septemlineatuscomb. nov. showed considerable genetic divergence from their recognized congeners (uncorrected P-distance ≥3.9%). Furthermore, the new species and H. septemlineatuscomb. nov. can be diagnosed from closely related congeners by a combination of pholidosis characters.


Assuntos
Colubridae/anatomia & histologia , Colubridae/genética , Filogenia , Escamas de Animais , Animais , China , Feminino , Masculino , Especificidade da Espécie
19.
Zool Res ; 42(4): 487-491, 2021 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-34235897

RESUMO

A new species of the genus Gonyosoma Wagler, 1828 is described herein based on six specimens from the Diaoluoshan Mountains, Hainan Island, Hainan Province, China. The new species, Gonyosoma hainanensesp. nov., is most similar to its continental sister species, Gonyosoma boulengeri (Mocquard, 1897). Both taxa have a scaled protrusion on the anterior portion of the rostrum, distinct from other congeners. However, Gonyosoma hainanensesp. nov. can be distinguished from G. boulengeri by two significant morphological characters: (1) black orbital stripe absent in adults (vs. present in G. boulengeri); and (2) two loreals (vs. one loreal in G. boulengeri). The new species is also genetically divergent and forms a unique clade from its sister species and all other congeners based on sequences of the mitochondrial gene cytochrome b (cyt b).


Assuntos
Colubridae/anatomia & histologia , Colubridae/classificação , Animais , China , Colubridae/genética , DNA/genética , Feminino , Genômica , Masculino , Filogenia , Especificidade da Espécie
20.
Mol Phylogenet Evol ; 163: 107218, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34082130

RESUMO

Montane frogs of the genus Quasipaa Dubois, 1992 occur from southern China to Southeast Asia (Frost 2021). Analyses of mtDNA (Cytb) and nuDNA data (Rag1, Rag2, Rhod, Tyr) for samples from 93 localities throughout its distribution yield a phylogeny. Clades A and B occur in Southeast Asia, clade C in northern Yangtze River, China, clade D in southwestern China, and clades E and F in southeastern China. Results place Q. yei within monophyletic Quasipaa and identify two new species. Based on nuDNA data, the basal split of clade A and B indicates an Indochinese origin of Quasipaa. The west-east diversification of five species across South China (Q. spinosa, Q. exilispinosa, Q. jiulongensis, Q. shini, Q. boulengeri) corresponds to topographic terrains II and III of China. Divergence of species from southeastern China (Q. shini, Q. jiulongensis, Q. spinosa, Q. exilispinosa) and southwestern China (Q. boulengeri) dates to 15.30-16.56 Ma (million years ago). A principal component analysis (PCA) and t-test involving 19 bioclimatic variables identifies significantly different environmental conditions between the two regions. Species' distribution models (SDM) for Q. spinosa and Q. boulengeri identify the best areas to be eastern and western South China, respectively. Thus, environmental variation appears to have influenced the genetic divergence and distributions of Quasipaa in South China. Mito-nuclear discordance indicates that some individuals of Q. exilispinosa and Q. spinosa hybridized historically.


Assuntos
Anuros , DNA Mitocondrial , Animais , Anuros/genética , Núcleo Celular , China , DNA Mitocondrial/genética , Humanos , Filogenia
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